Methods for oxidative coupling of methane using metal oxide catalysts and a sulfur oxidant.

A process for the preparation of an alkene from an oxygenate comprising contacting a reactant feedstream comprising at least one oxygenate reactant and water with a supported heteropolyacid catalyst at a temperature of at least 170° C., wherein the process is initiated using a start-up procedure comprising the following steps: (i) heating the supported heteropolyacid catalyst to a temperature of at least 220° C.; (ii) maintaining the heat-treated supported heteropolyacid catalyst of step (i) at a temperature of at least 220° C. for a time sufficient to remove bound water from the heteropolyacid component of the supported heteropolyacid catalyst; (iii) under an anhydrous atmosphere, reducing the temperature of the heat-treated supported heteropolyacid catalyst of step (ii) to a temperature below 220° C.; and (iv) contacting the supported heteropolyacid catalyst of step (iii) with the reactant feedstream at a temperature of at least 170° C.

The present invention relates to catalyst comprising at least one transition metal selected from Group VIA and Group VITA metals and a support containing a mixture of 0.1 to 60 percent by weight of zeolite, based on total weight of the support, with at least one other inorganic or organic material, wherein the at least one other inorganic or organic material is selected from silicon dioxide, titanium dioxide, zirconium dioxide and activated carbon, preferably silicon dioxide; and a process for olefin metathesis utilizing that catalyst.

The present invention relates to a catalyst system for olefin metathesis, the catalyst system comprising: a) a first system zone substantially comprising a layered double hydroxide; and b) a second system zone comprising a metathesis catalyst.

An active material useful in an oxidative dehydrogenation reactor system has an active phase, and a mixed metal oxide support phase. The active phase includes a transition metal oxide such as manganese oxide, which is reversibly oxidizable and/or reducible between oxidized and reduced states. The support phase includes a mixed metal oxide of a two or more IUPAC Group 2-14 elements. The active phase can also include a promoter such as Na-WO4 and/or a selectivity modifier such as Al or ceria. Also, a reactor including the active material in a reactor, a method of making the active material, and a method of using the active material in a regenerative reaction process.

Embodiments of processes and multiple-stage catalyst systems for producing propylene comprising introducing a hydrocarbon stream comprising 2-butene to an isomerization catalyst zone to isomerize the 2-butene to 1-butene, passing the 2-butene and 1-butene to a metathesis catalyst zone to cross-metathesize the 2-butene and 1-butene into a metathesis product stream comprising propylene and C.sub.4-C.sub.6 olefins, and cracking the metathesis product stream in a catalyst cracking zone to produce propylene. The isomerization catalyst zone comprises a silica-alumina catalyst with a ratio by weight of alumina to silica from 1:99 to 20:80. The metathesis catalyst comprises a mesoporous silica catalyst support impregnated with metal oxide. The catalyst cracking zone comprises a mordenite framework inverted (MFI) structured silica catalyst.

Embodiments of methods of synthesizing a metathesis catalyst system, which include impregnating tungsten oxide on silica support in the presence of a precursor to produce a base catalyst; calcining the base catalyst; impregnating a metal oxide co-catalyst comprising a metal oxide onto the surface of the base catalyst to produce a doped catalyst; and calcining the doped catalyst to produce a metathesis catalyst system. Further embodiments of processes for the production of propylene, which include contacting a hydrocarbon feedstock comprising a mixture of 1-butene and 2-butene with embodiments of the metathesis catalyst system to produce, via metathesis conversion, a product stream comprising propylene.

Embodiments of methods of synthesizing a metathesis catalyst system, which include impregnating tungsten oxide on silica support in the presence of a precursor to produce a base catalyst; calcining the base catalyst; dispersing a solid metal-based co-catalyst onto the surface of the base catalyst to produce a doped catalyst; and calcining the doped catalyst to produce a metathesis catalyst system. Further embodiments of processes for the production of propylene, which include contacting a hydrocarbon feedstock comprising a mixture of 1-butene and 2-butene with embodiments of the metathesis catalyst system to produce, via metathesis conversion, a product stream comprising propylene.

Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.

Disclosed is a method for production of synthesis gas and ethylene by a combined oxidative coupling and dry reforming of methane process. Heat generated from the oxidative coupling of methane can be used to drive the endothermic dry reforming of methane reaction.